In wired telecommunication systems such as in cable television, coaxial cables are typically utilized for transmitting electronic signals across a distance between two fixed points. To build a network of such cables, it is desirable to possess an efficient and effective means for coupling coaxial cables with other devices such as other pieces of cable, signal conditioners, receivers, encoders/decoders, amplifiers, splitters, multitaps, and junction boxes which may be located at either end of a run of a coaxial cable or at any other location therebetween. It is even more critical to provide a reliable and effective mechanical and electrical connection between the cable and the corresponding electrical device so that there is little impedance mismatch and signal attenuation or loss caused by the connection therebetween, and that there is little radio frequency interference from the outside or signal leakage from the inside to the outside.
The typical electrical device used in coaxial cable systems includes an electrically grounded chassis with one or more female input and/or output ports extending therefrom. Each of the female ports further includes a coupling assembly with one end electrically connected to internal circuitry housed within the chassis and the other end having a seizing mechanism for receiving and retaining an end of a coaxial cable which when properly connected, electrical engagement is made between a center conductor of the cable with the internal circuitry housed inside the chassis.
A reliable way to couple a coaxial pin connector to a connecting port for a device is desired for devices such as those mounted on top of utility poles, or in other inaccessible areas. Such devices are typically subject to temperature extremes, making reliability and ease of use essential.
In the prior art, to install a pin connector into device, an installer first tightens a connector to each of the input and output ports of the device, respectively, and then secures each connector pin of a respective connector with a seizure screw located in the associated port. Often the pin is scored or bent by the force of the seizure screw, causing physical damage to the pin. The pin is weakened, and the plating on the pin deteriorates. Also, the electrical connection is mainly with the small area of the screw, and the seizure block. Usually the device is prepared at ground level for attachment of the pin connectors at the input and output ports. Thereafter, the device with pin connectors is installed near the top of a utility pole. Next the input and output coaxial cable ends are secured to the pin connectors at the input and output ports, respectively, of the device by locking nuts on each connector. Usually, when the cables are so secured, the tightening process causes the pins of the connectors to undergo excessive torque, twisting the respective seizure assembly, and often damaging the associated assembly.
One example of the electrical device described above, is a multi-tap device, or simply multi-tap. Multi-taps are used primarily in cable television systems to tap off RF signals and AC power from a main distribution cable for bringing television or RF signals to multiple subscribers through secondary coaxial drops. The multi-tap permits connection to the main RF signal carrying cable, and provides multiple outputs for individual connection to a number of subscribers, respectively. During installation, it is a common practice to pass the main cable into one multi-tap at a female input port thereof, and to continue the main cable from a female output of the multi-tap for connecting the input port of a next multi-tap down line and so on.
In the past, coaxial cables were simply coupled to the female ports by inserting the center conductor or a pin of an associated connector into a receiving slot of the seizing mechanism where a retaining screw is tightened onto the conductor for mechanical retainment and electrical connection thereto. In response to increased telecommunication subscriberships as well as robust demand for larger bandwidths, coaxial cables particularly the center conductor portions have become progressively larger. The increased diameter of coaxial cables has led to the use of male coaxial cable connectors with center pins compatible with seizing mechanisms of the corresponding electrical devices for accommodating the larger size center conductors and cables, and providing a means for connecting ever increasing diameter coaxial cables to already existing female ports of the electrical devices including multi-taps.
The prior art seizing mechanisms suffer from serious drawbacks which limit the effectiveness of the mechanical retainment and electrical connection with the center conductor of the coaxial cable or the center pin of the male coaxial connector. Sometimes, the installer through improper installment procedures, may tighten the retaining screw within the seizing mechanism prior to tightening the coupling between the connector and the female port. When the installer subsequently applies torque to the connector to install an external coaxial cable, excessive twisting force is transferred to the center pin where either the center pin fails or the seizing mechanism is damaged. Temperature effects may also contribute to failure, whereby as the temperature changes, the center pin elongates in response to heat or contracts in response to cold. The stress associated by such physical changes as the center pin is rigidly held by the retaining screw can lead to compromised electrical contact and even complete failure.
For the foregoing reasons, there is a need for an improved female connecting port assembly of an electrical device, that can overcome all of the limitations described above in a cost effective and efficient manner. One benefit of such a connecting port is that it can provide electrical connection with a range of center pins or conductors of varying industry-accepted tolerances thereby minimizing damage to the connecting port assembly and/or to the center pin or conductor. This further enables the connecting port assembly to accommodate any physical changes in the center pin whether induced by the material, the temperature or the installer. Furthermore, the resulting contact between the connecting port and the center pin provides for a much improved connection with better electrical signal quality and reliability.